1. Field of the Invention
The present invention relates to a dual-disc type of tool turret device of a machine, more particularly one, which is powered so as to carry out a tool-choosing action of either of inner and outer tool turrets thereof by means of single main power source of the machine, which serves to power the spindle of the machine.
2. Brief Description of the Prior Art
The inventor of the present invention invented a twin disk type tool turret mechanism for CNC machines before, which was granted U.S. Pat. No. 7,010,839. The twin disk type tool turret mechanism includes internal and external tool turrets, a toothed ring secured to the internal tool turret, a central shaft secured to the external turret, a power switch, and a clutch; the central shaft has a piston fitted thereto; the power switch is used for providing power to the internal and the external turrets through the toothed ring and the shaft respectively; the clutch includes a fixed clutch claw, external and internal ring clutch claws, which are respectively securely connected to inner edge of the internal turret, and inner edge of the external turret; the ring clutch claws will rotate, and engage each other; when the piston is actuated, and displaced, the external turret will be forced to change position, and both the turrets will be left and right displaced between a first position, in which they engage the clutch, and a second position, in which they disengage the clutch. In summary, either of the internal and the external turrets is chosen, and the chosen turret will be rotated for choosing a tool therefrom subsequently.
The inventor of the present invention also invented a twin disc type tool turret device of a machine, which was filed for patent application, with application Ser. No. 11/128,204, now U.S. Pat. No. 7,263,915. The twin disc type tool turret device includes a central shaft, a piston sleeve positioned around the central shaft and having moving sticks thereon, a push rod, an actuating seat, and internal and external turrets; the piston sleeve is actuated to move left and right by means of a power source; the moving sticks are passed through a ringed sleeve, which props a push rod passed through a fixed clutch claw, and facing the actuating seat; the actuating seat includes a rotary shaft, a pivotal shaft, and a toothed ring seat; the piston sleeve can be moved such that the moving sticks and the push rod move forwards, and the rotary shaft engages the toothed ring seat for a tool of a straight tool seat to function; alternatively the piston sleeve can be moved such that the moving sticks and the push rod move backwards, and the rotary shaft disengages the toothed ring seat for allowing replacement of the toothed ring seat.
The above two devices have the following drawbacks:
1. The devices each have to be provided with two power sources therefore the cost is high.
2. The devices each have to be provided with two power sources, which would occupy much space together.
3. They have to be equipped with a switching device to choose between the two power sources in order for one of the internal and external turrets to be rotated.
4. The spindle length is relatively short, and the spindle is too close to the bed. Consequently, it isn't possible for other tools to be provided in a reverse direction without interference, which would cause damage to the machine as well as the tools; in other words, machining action is only allowed in a forward direction.